In the list of your store's payment methods, locate the name of the PayPal payment method you use currently and click the Delete link next to it. The method will be removed.

Note: If you use PayPal Payments Advanced, PayPal Payments Pro (via Payflow API or PayPal API) or Payflow Link, your store's list of payment methods on the 'Payment methods' page contains two entries for PayPal. One of them is your payment option allowing your customers to pay you using a PayPal account via the Express Checkout button (by default, the name of this method is displayed as 'PayPal'); the other one is your method for processing credit and debit card payments (by default, the name of this method is displayed as 'Credit or Debit card'). Provided that you see two PayPal payment methods in your store's Payment methods list, you should use the Delete link displayed next to the 'Credit and Debit card' entry to remove both the methods.

Note that, if you add PayPal to the list of your store's payment methods again after PayPal has been removed from there, the PayPal solution and the configuration settings used by the restored PayPal payment method will be the same as in the PayPal payment method that was removed.